I have a friends '91 7.3n/a to work on, it wouldn't start. he already installed the return line kit as i told him to do, he also installed a new supply pump. it already had a new g-p controller, new g-ps'-yes the good ones ZD-9s'(they put 1 an' i put 7 more!) and a new fuel filter. Someone also replaced the #1 injector line and i guess it was to hard to fit back in regular form so they bent it a little and now where it seats on the injector; one side of the seating area has a deep scar. i tried to re-dress the seat with a fine file and came out really well(it doesn't leak now) but the line still doesn't fit in uniform with the others so the vibration clamp that wasn't even there can't be installed
My questions are:
should i replace the line anyway?
There is crud/sediment buildup in the intake from the cdr; do i try and clean it out? (the intake)
How can i tell if the cdr. is coming apart?
Compression is about 310-320psi after 3 revolutions and will climb to 400 on most cylinders with only one staying around around 360; is this o-k or do i worry about the one cyl?
The return fitting going from the top of the filter housing is open/orifice,there is no check valve-correct?

thanks for any info
by the way it does run now

 

Did they put the timing adapter back on the #1 line.......... it would be about 2.5 inches too short otherwise.....

Comp tests are uaually done on warm engine.....record your numbers and add 25 psi for a start point if you did it cold.

I will PM you CDR info it's been posted 100 times.

return to the filter header from #1 has a check ball and spring inside, to stop fuel from returning but allow air to exit the filter header via return lines.

 

thanks PLC7.3, i did the comp test on a hot engine and sorry about the ever redundant cdr question.
the fitting on filter header is orificed but no check inside.
i don't understand about the timing adapter plate on #1; the pump he installed was the supply pump. Neither of us has removed the i-p although it looks like it has been replaced the marks are aligned.

 

on the #1 cylinder , there is an adapter for pulse timing (on the pickup engines, the van engine has it somewhere else). it is about 2 inches tall and will make the difference in installing the #1 injection line if it is missing.

 

gotcha, now i know what it is and what it does and no it's not there.